Displays are used in a very wide range of applications, including entertainment (e.g., television, e-books), advertisement (e.g., shopping malls, airports, billboards), information (e.g., automotive, avionics, system monitoring, security), and cross-applications (e.g., computers, smart phones). As such, displays are generally subject to a wide range of viewing environments, and in many applications the viewing environment of the display is not a constant.